Mirror transitions in diffusion with stochastic resetting confined on a ring

TL;DR

This study analyzes how stochastic resetting at multiple sites on a ring affects the mean first-passage time to a target, revealing complex phase transitions and symmetry effects.

Contribution

It introduces a framework for optimizing resetting strategies in bounded circular domains with multiple resetting sites, highlighting phase transition phenomena.

Findings

Optimal resetting rate can show abrupt ('first order') and continuous ('second order') transitions.

The mean first-passage time behavior includes critical and tri-critical points.

Transitions exhibit mirror symmetry around the target site.

Abstract

Diffusion with an incorporated resetting mechanism provides a reference framework for modeling a wide range of natural phenomena. Within this framework, the optimal resetting rate is a key quantity that arises from the optimization of the mean first-passage time. While substantial work has focused on the study of the optimal resetting rate in unbounded one dimensional domains, little is still known about the optimization of the mean first-passage time in bounded systems, in particular when multiple resetting sites are available. In this work, we consider a particle diffusing along a circular circumference and under resetting, with an absorbing target site at a fixed location. Using the appropriate free propagator for this system, we compute the Laplace transform of the survival probability when resetting occurs to multiple sites drawn from an arbitrary probability density function. We also calculate the mean first-passage time at the target site, and study the dependence of the optimal resetting rate in terms of the relevant parameters of the system in a two-resetting site configuration. Depending on the arc length between one of the resetting sites and the absorbing target site, and the weight of the remaining resetting site, the optimal resetting rate can exhibit abrupt ("first order'') and continuous ("second order'') transitions. Moreover, the behavior of the mean first-passage time is rich enough to allow both critical and tri-critical points to exist in the parameter space. All the transitions have "mirror symmetry'' around the selected target site and its corresponding diametrically opposite site.